The present invention builds on the task (1) to reduce in the case of coating installations, for example with virtually continuous 24-hour production operation, the shutdown times for maintenance, such as, for example, for replacing material sources consumed during the coating process or other installation parts such as coating masks. Therein (2) the coating installation should be constructionally as simple and compact as feasible.
Coating installations conventionally comprise a transport chamber, wherein, in the simplest case, workpieces are transported from an input/output lock station to a coating station. They are therein coated and subsequently transported back to the input/output lock station. Based on the requirement (2) for the simplest possible concept, a pump unit is provided via a pump opening on the transport chamber, which simultaneously handles the evacuation of the treatment station. Thus, in installations of this type the transport chamber is also flooded during the flooding of the treatment station. Otherwise the coating station would need to be compartmentalizable with respect to the transport chamber by employing a relatively complicated valve device.
A critical extension of the production shutdown times during the flooding of coating station and transport chamber results therefrom that, together with the transport chamber, at least portions of the pump unit flanged onto the pump opening are flooded. This leads, for one, to relatively long reconditioning times for the resumption of operation. For another, when, for example, turbovacuum pumps are provided on the pump unit, the latter would have to be compartmentalized against the flooding, which requires complicated and expensive compartmentalization valves.